1. What is BMI?

Body Mass Index (BMI) is a simple calculation using a person's height and weight. The formula is BMI = kg/m² where kg is a person's weight in kilograms and m² is their height in meters squared. It's widely used in Australia as a screening tool for eating disorders and weight categories.

2. How Does the Calculator Work?

The calculator uses the standard BMI formula:

Where:

• \( weight \) — Body weight in kilograms (kg)
• \( height \) — Height in meters (m)

Explanation: BMI provides a simple numeric measure of a person's thickness or thinness, allowing health professionals to discuss weight problems more objectively with their patients.

3. Importance of BMI Calculation

Details: BMI is particularly important in eating disorder screening and management. In Australia, it's used to assess underweight, healthy weight, overweight, and obesity categories which can indicate potential eating disorders or weight-related health risks.

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. For accuracy, measure weight when fasting and height without shoes. All values must be valid (weight > 0, height > 0).

5. Frequently Asked Questions (FAQ)

Q1: What are the BMI categories in Australia?
A: Underweight (<18.5), Healthy weight (18.5-24.9), Overweight (25-29.9), Obese (≥30).

Q2: How is BMI used in eating disorder assessment?
A: Low BMI may indicate anorexia nervosa, while high BMI may indicate binge eating disorder. However, BMI alone doesn't diagnose eating disorders.

Q3: What are limitations of BMI?
A: BMI doesn't distinguish between muscle and fat, and may not be accurate for athletes, pregnant women, or certain ethnic groups.

Q4: Should children use this calculator?
A: Children need age- and sex-specific BMI percentile charts rather than adult categories.

Q5: How often should BMI be checked?
A: For eating disorder monitoring, weekly measurements may be needed. For general health, annual checks are typically sufficient.